[SYCL][Driver] Enforce unique filenames when -save-temps is used

clang/include/clang/Driver/Driver.h

@@ -540,6 +540,11 @@ class Driver {
   /// GCC goes to extra lengths here to be a bit more robust.
   std::string GetTemporaryPath(StringRef Prefix, StringRef Suffix) const;
 
+  /// GetUniquePath = Return the pathname of a unique file to use
+  /// as part of compilation. The file will have the given base name (BaseName)
+  /// and extension (Ext).
+  std::string GetUniquePath(StringRef BaseName, StringRef Ext) const;
+
   /// GetTemporaryDirectory - Return the pathname of a temporary directory to
   /// use as part of compilation; the directory will have the given prefix.
   std::string GetTemporaryDirectory(StringRef Prefix) const;

clang/lib/Driver/Driver.cpp

@@ -6071,21 +6071,38 @@ const char *Driver::GetNamedOutputPath(Compilation &C, const JobAction &JA,
     NamedOutput = C.getArgs().MakeArgString(TempPath.c_str());
   }
 
-  // If we're saving temps and the temp file conflicts with the input file,
-  // then avoid overwriting input file.
-  if (!AtTopLevel && isSaveTempsEnabled() && NamedOutput == BaseName) {
-    bool SameFile = false;
-    SmallString<256> Result;
-    llvm::sys::fs::current_path(Result);
-    llvm::sys::path::append(Result, BaseName);
-    llvm::sys::fs::equivalent(BaseInput, Result.c_str(), SameFile);
-    // Must share the same path to conflict.
-    if (SameFile) {
-      StringRef Name = llvm::sys::path::filename(BaseInput);
-      std::pair<StringRef, StringRef> Split = Name.split('.');
-      std::string TmpName = GetTemporaryPath(
+  if (isSaveTempsEnabled()) {
+    // If we're saving temps and the temp file conflicts with any
+    // input/resulting file, then avoid overwriting.
+    if (!AtTopLevel) {
+      bool SameFile = false;
+      SmallString<256> Result;
+      llvm::sys::fs::current_path(Result);
+      llvm::sys::path::append(Result, BaseName);
+      llvm::sys::fs::equivalent(BaseInput, Result.c_str(), SameFile);
+      // Must share the same path to conflict.
+      if (SameFile) {
+        StringRef Name = llvm::sys::path::filename(BaseInput);
+        std::pair<StringRef, StringRef> Split = Name.split('.');
+        std::string TmpName = GetTemporaryPath(
+            Split.first, types::getTypeTempSuffix(JA.getType(), IsCLMode()));
+        return C.addTempFile(C.getArgs().MakeArgString(TmpName));
+      }
+    }
+
+    const auto &ResultFiles = C.getResultFiles();
+    const auto CollidingFilenameIt =
+        llvm::find_if(ResultFiles, [NamedOutput](const auto &It) {
+          return StringRef(NamedOutput).equals(It.second);
+        });
+    if (CollidingFilenameIt != ResultFiles.end()) {
+      // Upon any collision, a unique hash will be appended to the filename,
+      // similar to what is done for temporary files in the regular flow.
+      StringRef CollidingName(CollidingFilenameIt->second);
+      std::pair<StringRef, StringRef> Split = CollidingName.split('.');
+      std::string UniqueName = GetUniquePath(
           Split.first, types::getTypeTempSuffix(JA.getType(), IsCLMode()));
-      return C.addTempFile(C.getArgs().MakeArgString(TmpName));
+      return C.addResultFile(C.getArgs().MakeArgString(UniqueName), &JA);
     }
   }
 
@@ -6215,6 +6232,18 @@ std::string Driver::GetTemporaryPath(StringRef Prefix, StringRef Suffix) const {
   return std::string(Path.str());
 }
 
+std::string Driver::GetUniquePath(StringRef BaseName, StringRef Ext) const {
+  SmallString<128> Path;
+  std::error_code EC = llvm::sys::fs::createUniqueFile(
+      Twine(BaseName) + Twine("-%%%%%%.") + Ext, Path);
+  if (EC) {
+    Diag(clang::diag::err_unable_to_make_temp) << EC.message();
+    return "";
+  }
+
+  return std::string(Path.str());
+}
+
 std::string Driver::GetTemporaryDirectory(StringRef Prefix) const {
   SmallString<128> Path;
   std::error_code EC = llvm::sys::fs::createUniqueDirectory(Prefix, Path);

clang/test/Driver/sycl-offload.c

@@ -749,22 +749,25 @@
 // RUN: %clang -fsycl -target x86_64-unknown-linux-gnu -save-temps %s -### 2>&1
 // RUN: %clang -fsycl -fsycl-targets=spir64-unknown-unknown-sycldevice -target x86_64-unknown-linux-gnu -save-temps %s -### 2>&1
 // RUN: %clangxx -fsycl -fsycl-targets=spir64-unknown-unknown-sycldevice -target x86_64-unknown-linux-gnu -save-temps %s -### 2>&1 \
-// RUN: | FileCheck %s --check-prefix=CHK-FSYCL-SAVE-TEMPS
+// RUN: | FileCheck %s --check-prefixes=CHK-FSYCL-SAVE-TEMPS,CHK-FSYCL-SAVE-TEMPS-CONFL
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-fsycl-is-device"{{.*}} "-o" "[[DEVICE_BASE_NAME:[a-z0-9-]+]].ii"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-fsycl-is-device"{{.*}} "-o" "[[DEVICE_BASE_NAME]].bc"{{.*}} "[[DEVICE_BASE_NAME]].ii"
-// CHK-FSYCL-SAVE-TEMPS: llvm-link{{.*}} "[[DEVICE_BASE_NAME]].bc"{{.*}} "-o" "[[DEVICE_BASE_NAME]].bc"
-// CHK-FSYCL-SAVE-TEMPS: sycl-post-link{{.*}} "-o" "[[DEVICE_BASE_NAME]].table" "[[DEVICE_BASE_NAME]].bc"
+// CHK-FSYCL-SAVE-TEMPS: llvm-link{{.*}} "[[DEVICE_BASE_NAME]].bc"{{.*}} "-o" "[[LINKED_DEVICE_BC:.*\.bc]]"
+// CHK-FSYCL-SAVE-TEMPS-CONFL-NOT: "[[DEVICE_BASE_NAME]].bc"{{.*}} "[[DEVICE_BASE_NAME]].bc"
+// CHK-FSYCL-SAVE-TEMPS: sycl-post-link{{.*}} "-o" "[[DEVICE_BASE_NAME]].table" "[[LINKED_DEVICE_BC]]"
 // CHK-FSYCL-SAVE-TEMPS: file-table-tform{{.*}} "-o" "[[DEVICE_BASE_NAME]].txt" "[[DEVICE_BASE_NAME]].table"
-// CHK-FSYCL-SAVE-TEMPS: llvm-foreach{{.*}} "-o" "[[DEVICE_BASE_NAME]].txt" {{.*}} "[[DEVICE_BASE_NAME]].txt"
-// CHK-FSYCL-SAVE-TEMPS: file-table-tform{{.*}} "-o" "[[DEVICE_BASE_NAME]].table" "[[DEVICE_BASE_NAME]].table" "[[DEVICE_BASE_NAME]].txt"
-// CHK-FSYCL-SAVE-TEMPS: clang-offload-wrapper{{.*}} "-o=[[TEMPFILE:[a-z0-9_/-]+]].bc"{{.*}} "-batch" "[[DEVICE_BASE_NAME]].table"
-// CHK-FSYCL-SAVE-TEMPS: llc{{.*}} "-o" "[[DEVICE_OBJ_NAME:[a-z0-9\-]+]].o"{{.*}} "[[TEMPFILE]].bc"
+// CHK-FSYCL-SAVE-TEMPS: llvm-foreach{{.*}}llvm-spirv{{.*}} "-o" "[[SPIRV_FILE_LIST:.*\.txt]]" {{.*}}"[[DEVICE_BASE_NAME]].txt"
+// CHK-FSYCL-SAVE-TEMPS-CONFL-NOT: "-o" "[[DEVICE_BASE_NAME]].txt" {{.*}}"[[DEVICE_BASE_NAME]].txt"
+// CHK-FSYCL-SAVE-TEMPS: file-table-tform{{.*}} "-o" "[[PRE_WRAPPER_TABLE:.*\.table]]" "[[DEVICE_BASE_NAME]].table" "[[SPIRV_FILE_LIST]]"
+// CHK-FSYCL-SAVE-TEMPS-CONFL-NOT: "-o" "[[DEVICE_BASE_NAME]].table"{{.*}} "[[DEVICE_BASE_NAME]].table"
+// CHK-FSYCL-SAVE-TEMPS: clang-offload-wrapper{{.*}} "-o=[[WRAPPER_TEMPFILE_NAME:[a-z0-9_/-]+]].bc"{{.*}} "-batch" "[[PRE_WRAPPER_TABLE]]"
+// CHK-FSYCL-SAVE-TEMPS: llc{{.*}} "-o" "[[DEVICE_OBJ_NAME:.*\.o]]"{{.*}} "[[WRAPPER_TEMPFILE_NAME]].bc"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-fsycl-is-device"{{.*}} "-fsycl-int-header=[[DEVICE_BASE_NAME]].h"{{.*}} "[[DEVICE_BASE_NAME]].ii"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-include" "[[DEVICE_BASE_NAME]].h"{{.*}} "-fsycl-is-host"{{.*}} "-o" "[[HOST_BASE_NAME:[a-z0-9_-]+]].ii"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-o" "[[HOST_BASE_NAME:.*]].bc"{{.*}} "[[HOST_BASE_NAME]].ii"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-o" "[[HOST_BASE_NAME:.*]].s"{{.*}} "[[HOST_BASE_NAME]].bc"
 // CHK-FSYCL-SAVE-TEMPS: clang{{.*}} "-o" "[[HOST_BASE_NAME:.*]].o"{{.*}} "[[HOST_BASE_NAME]].s"
-// CHK-FSYCL-SAVE-TEMPS: ld{{.*}} "[[HOST_BASE_NAME]].o"{{.*}} "[[DEVICE_OBJ_NAME]].o"
+// CHK-FSYCL-SAVE-TEMPS: ld{{.*}} "[[HOST_BASE_NAME]].o"{{.*}} "[[DEVICE_OBJ_NAME]]"
 
 /// -fsycl with /Fo testing
 // RUN: %clang_cl -fsycl /Fosomefile.obj -c %s -### 2>&1 \

sycl/test/regression/fsycl-save-temps.cpp

@@ -0,0 +1,25 @@
+//==--------------- fsycl-save-temps.cpp -----------------------------------==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// Verify that a sample compilation succeeds with -save-temps
+// RUN: %clangxx -fsycl -save-temps %s -o %t.out
+
+#include <CL/sycl.hpp>
+
+void foo() {}
+
+int main() {
+  cl::sycl::queue Q;
+  Q.submit([](cl::sycl::handler &Cgh) {
+    Cgh.single_task<class KernelFunction>([]() { foo(); });
+  });
+  return 0;
+}
+
+// TODO: Address a Windows-specific issue with integration header filenames
+// XFAIL: system-windows